Add B2B reformista panel with Postgres/Drizzle data layer

Modela el funnel del lead en dos dimensiones (pipeline_stage técnico
de 7 pasos + estado comercial de 6 estados) y siembra 11 leads demo,
uno por cada momento del funnel, para analizar el siguiente paso.
Incluye panel /panel (lista + detalle RF-D-01/02) y wiring de deploy
(Dockerfile multi-stage + entrypoint migrate+seed).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

mvp/b2c/src/db/queries.ts

@@ -0,0 +1,66 @@
+import { and, asc, desc, eq } from 'drizzle-orm';
+import { db } from './index';
+import {
+  leads,
+  leadFotos,
+  leadEstadoHistory,
+  leadPipelineEventos,
+  precisionHistory,
+  tenants,
+} from './schema';
+import { TENANT_SLUG } from '@/lib/funnel';
+
+async function getTenantId(): Promise<string> {
+  const [tenant] = await db.select().from(tenants).where(eq(tenants.slug, TENANT_SLUG)).limit(1);
+  if (!tenant) throw new Error(`Tenant "${TENANT_SLUG}" no existe. ¿Has corrido npm run db:seed?`);
+  return tenant.id;
+}
+
+export type LeadFiltro = (typeof leads.estado.enumValues)[number] | 'todos';
+
+export async function getLeads(filtro: LeadFiltro = 'todos') {
+  const tenantId = await getTenantId();
+  const where =
+    filtro === 'todos'
+      ? eq(leads.tenantId, tenantId)
+      : and(eq(leads.tenantId, tenantId), eq(leads.estado, filtro));
+
+  return db.select().from(leads).where(where).orderBy(desc(leads.createdAt));
+}
+
+export async function getLead(id: string) {
+  const tenantId = await getTenantId();
+  const [lead] = await db
+    .select()
+    .from(leads)
+    .where(and(eq(leads.id, id), eq(leads.tenantId, tenantId)))
+    .limit(1);
+
+  if (!lead) return null;
+
+  const [fotos, eventos, historial, precision] = await Promise.all([
+    db.select().from(leadFotos).where(eq(leadFotos.leadId, id)).orderBy(asc(leadFotos.orden)),
+    db
+      .select()
+      .from(leadPipelineEventos)
+      .where(eq(leadPipelineEventos.leadId, id))
+      .orderBy(asc(leadPipelineEventos.occurredAt)),
+    db
+      .select()
+      .from(leadEstadoHistory)
+      .where(eq(leadEstadoHistory.leadId, id))
+      .orderBy(asc(leadEstadoHistory.changedAt)),
+    db.select().from(precisionHistory).where(eq(precisionHistory.leadId, id)),
+  ]);
+
+  return { lead, fotos, eventos, historial, precision: precision[0] ?? null };
+}
+
+export async function getResumen() {
+  const all = await getLeads('todos');
+  const porEstado = all.reduce<Record<string, number>>((acc, l) => {
+    acc[l.estado] = (acc[l.estado] ?? 0) + 1;
+    return acc;
+  }, {});
+  return { total: all.length, porEstado };
+}